Survival of medically treated thalassemia patients in Cyprus. Trends and risk factors over the period 1980-2004

Department of Paediatric Haematology and Oncology, St. Bartholomew's and The Royal London Hospitals NHS Trust, UK. paul.telfer@bartsandthelondon.nhs.uk

BACKGROUND AND OBJECTIVES: A large number of patients with thalassemia major have been born and treated exclusively in Cyprus. They have been managed according to standard international practice, but few have been transplanted. In 1999, a combination chelation regime with desferrioxamine and deferiprone was introduced. We analyzed survival trends in Cypriots and tried to identify factors associated with prolonged survival. DESIGN AND METHODS: We had incomplete information on births pre-1974 and complete information from 1974 onwards. Clinical data were incomplete pre-1980 and complete thereafter. We analyzed data on 539 patients born after 1960 and followed over the period 1980 to the end of 2004. RESULTS: There were 58 deaths, 31 (53.4%) of which where due to cardiac causes. In the complete birth cohort of 284 patients born after 1974, survival (95% CI) at 10, 20 and 30 years was 100% (0); 98.5% (96.1-99.4) and 92.7% (86.7-96.1) respectively. There was a significant trend of increasing cardiac deaths between 1980 and 2000 (p<0.001) and a decline after 2000 (p=0.06). In multivariate survival analysis, protective effects were found for female sex (hazard ratio, 0.37, 95% CI 0.21-0.66; p<0.001), and post-2000 follow-up (hazard ratio, 0.44, 95% CI 0.20-0.99; p<0.05), but not for genotype, treatment center or birth cohort. INTERPRETATION AND CONCLUSIONS: Most patients born after 1974 survive to at least the age of 30. There has been a marked improvement in survival for patients of all ages since 2000, which may be due to the introduction of combination chelation therapy.